The first form of earth energy is a dark kind of sexual energy that takes upon forms of lust and near that of the reptile / mammal brain, it's the earth energy vibe which heals everything inside the body/mind mechanism and that is why 'Lust is evil' because those who have alot of lust are also very damaged emotionally, as the first way to healing is getting in contact with this lust-vibe which is really the earth-vibe.
Though there are of course odd harmonies of this vibe that can take upon absurd proportions and lead to odd results, but generally it's a very healing vibe and making that inner demon connect to the lust and giving it the sexual-ride of it's life-time makes that area of the emotional body healed and integrated, so it's really a form of love in a more primitive vibrational form.
In this case primitivity doesn't mean that it's bad or evil. For example the reptile brain inside is so primitive that it has no concept of lying or cheating, and can simply not do it because it doesn't exist in it's world, but then again the human brain part knows all those things
The first connection point for the earth energy is the feet and then the spine beginning, and it's form is different shades of lust and desire and it's very pleasurable to go through them and one gets healed at the same time, the same energy when arised further becomes forms of love and so forth
But like all good 'spiritual people' I also thought that all forms of lust and desire are outright evil and bad and had to actually struggle to get away all those imprintions and programmings of my mind and noticed that no it's actually a good form of healing that happens if one accepts it and lets it and to be honest it seems like the different forms of lust and desire are there because one are neglecting patterns of ones own emotions, instead of going with them...